Datasheet Summary
SY81104/SY81104E
High Efficiency, 4A, 18V Input Synchronous Buck Converter
General Description
Features
The SY81104x high efficiency synchronous buck converter operates over a wide input voltage range of 4.5V to 18V, and can deliver an output current up to 4A. It integrates a top MOSFET and a bottom MOSFET with very low RDS(ON) to minimize conduction loss. The 400kHz pseudo-constant switching frequency enables using small external inductor and capacitor values.
The SY81104x uses constant on-time and ripple-based control strategy to achieve fast transient response for applications with high step-down ratios, and high efficiency at light loads. It also provides cycle-by-cycle current limit protection, output under voltage protection and over temperature protection.
Only the input and output capacitors, inductor, feedback resistor divider and feedforward capacitor need to be selected for the targeted application specifications.
The SY81104x is available in a pact TSOT23-6 package.
Part Number
SY81104ADT SY81104EADT
Package TSOT23-6
Frequency 400kHz
Light Load Operation Mode
PFM FCCM
- Low RDS(ON) for Internal MOSFETs: 29mΩ Top, 19mΩ Bottom
- Wide Input Voltage Range: 4.5V ~ 18V
- Up to 4A Output Current
- ±1% 0.6V Reference
- Pulse-Frequency Modulation (PFM) Mode
Operation for SY81104
- Forced Continuous Conduction Mode (FCCM)
Operation for SY81104E
- Internal Soft-Start Limits the Inrush Current
- Support Smooth Startup with Pre-Biased Output
- 400kHz Switching Frequency Minimizes the
External ponents
- Constant On-time and Ripple-Based Control to
Achieve Fast Transient Responses
- Output Auto-Discharge Function
- Cycle-by-Cycle Valley and Peak Current...